Evaluation of Modal and FEMA Pushover Analyses: Vertically “Regular” and Irregular Generic Frames

The accuracy of the nonlinear static procedure (NSP) using the lateral force distributions specified in the FEMA-356 document (ASCE 2000), now standard in engineering practice, and the recently developed dynamics-based modal pushover analysis (MPA) procedure (Chopra and Goel 2002) was evaluated in the companion paper by Goel and Chopra (2003). The median seismic demands were computed by these procedures for six SAC buildings, each analyzed for 20 ground motions, and compared with ‘‘exact’’ results obtained from nonlinear response history analysis (RHA).